First, welcome to the forum!
Yes, you can buy larger grip panels. The PPS is a "D" frame Colt, but not all D frames are the same. I'm not where I can look that up right now, but working from memory, I think any of the 2nd, 3rd, or 4th gen D frame grips will fit. Also, some of the after market stocks, such as Hogue are good if you're after a shooter.
Someone will be along soon to give you specifics.

PS: Best I can tell from your pics, the finish is nickel. Nice!

 

The easiest solution might be a grip adapter to get a more handfilling grip. There are some new "long frame" colt grips available in the market but it takes careful shopping to get the right ones with the rounded bottom corners and relieved for a full length grip frame.

 

They are small, basically the same size as an earlier, long framed, snubnose Detective Special. Maybe you can find some old, larger grips for your gun. Then it will feel better for shooting. But keep those wooden grips with it in storage, having original grips is better for collectors. Being nickle plated adds value to your gun, which is more desirable. It's not an expensive Colt, but nickle brings it up towards $500 or above.

 

It appears to be a long grip frame, so be careful when purchasing grips for a Detective Special. The short frame started in 1966.

 

I ain't much for nickel, but that thing looks just fine.
And I have to say, the wood looks pretty good too.
Put a grip adapter on it and see if it helps.
I once did it on a J frame S&W, and it made it at least shootable, although I did not like the thing in general.
I though it was the flimsiest S&W I ever had.

 

I, for one, love shiney!! Nice PP 38 spec. Thanks for posting pics.

 

Welcome to the forum. There are lots of people that can assist you with your questions.

 

In 1966 Colt changed all the "D" frame revolvers to the "Stubby" grip frame that uses grips that overlap on the bottom of the butt to give a full size grip.

Your Colt will have the older full length grip frame and that will make it more difficult to find a different style of grip.
Since this round butt type frame was discontinued in 1966, few after market grips were ever made, and very few are available today.
There are replica grips to fit your Colt, but they have the same size and shape as what's on the gun now.

Here's a few sources for the old style long frame grips:

https://www.eaglegrips.com/57-colt-pre-66-cobra-and-detective-grips

Collins will probably make you a custom set:

Custom Pistol Grips and Kits - CollinsCraftGrips

As above, one popular option is a grip adapter. This fills in the area between the front of the grip and the rear of the trigger guard, giving a larger grip.

Tyler Manufacturing and Distribution Company, Inc

Here's the difference in the pre-1966 "D" frame grip frame and and the post-1966 "stubby" grip frame.

 

Any idea if this would fit mine?
Pachmayr Grip for Colt Diamondback/Detective Special/Cobra/Agent 02513 | eBay

 

Any idea if this would fit mine?
Pachmayr Grip for Colt Diamondback/Detective Special/Cobra/Agent 02513 | eBay

No, it won't fit.
Pachmayr never made the Gripper type for the older long frame Colt.
They made a "Compac" type grip, and no longer make it.

The do still offer a long frame "Presentation" grip but it's made for the older Police Positive SQUARE butt.
This very possibly/probably "might" fit on your long round butt frame.

Pachmayr&reg Pachmayr your primary source for quality handgun grips and recoil pads

Again, finding a set of grips for the old long frame is not going to be easy.
One "watch-out" on buying Colt grips on the auctions is that the sellers seldom know what they have, and don't know about the different types of Colt grips.
Unless you're extremely careful you'll buy something and it'll turn out to be for the newer "stubby" frame.

 

Bump. Can anyone give me an appraisal on it? Its in great condition and shoots great. Thank you.

 

Hard to say without seeing the underside. But i'm pretty sure these will

Colt Detective Special Mustang Combat Wood Pistol Grips - NA14 | eBay

 

Oh boy here I go necroing a post lol, but seriously I would like to know if this is worth more than usual. I have only seen one nickle plated besides mine and it was ugly as hell.
If you look close you can literately see my fingers reflection by the grip. lol
If need be I could use this as a mirror to shave/etc.

Ok I found ONE and WOW. 470$? Looks rusty. COLT POLICE POSITIVE SPECIAL 38SPL REVOLVER 4” BBL NICKEL - Revolvers at GunBroker.com : 880252736

 

Ummmm NO

 

Go to "advanced" search. You have to do a completed auction, not a current auction.
Around $600.