I don't know either of the sellers, but there are at least two on ebay. There might be more.

By the time you buy all the parts, it would probably make more economical sense just to buy a Fuse and sell your P365. My 2¢ fwiw.

Edit to add; I forgot about the grip module and magazines. They are available lots of places.

OEM Sig Sauer P365 FUSE 9mm Complete Upper Slide Barrel Optic Ready X-Macro | eBay

Sig Sauer P365 FUSE Pro 9mm Slide Complete Upper Optic Ready Fiber Sight New, never fired. This fits any and every variation of a P365. It is ready to go onto the lower.

www.ebay.com

Pardon Our Interruption...

 

Easy to do start out with a P365 but you have to update a lot of stuff, so get a 4.3" barrel and slide and then a bigger grip or grip module to accommodate the 21 & 17 round magazines. Done!!!

Didn't do much research so not completely sure of all the dim's with the P365 Fuse, but FCU will swap from one grip to the other.

 

It's usually most economical to buy a new pistol. By the time you source the parts needed, you could buy the entire thing for a few hundred bucks

 

Fuse is around $800 complete new in the box.
Used P365 is worth maybe $400-450.
P365 FCU is $350 with flat trigger

You can buy a complete new takeoff Fuse slide on GB for about $400.
UncleTed2012 always has them on his store.

OEM new takeoff Fuse grip on GB with magwell is about another $100.

Mag extensions on Ebay to convert your P365 mags to Macro are another $15.

Hopefully you already have a flat trigger, if not and you really want it add another $50.
(Sig Guy has great videos of the process)

Total around $565 depending on shipping and tax of the parts.

I've built 3 this way myself.

You can sell your standard complete P365 slide and grip for maybe $300 on Ebay or GB.
If you do all that, it can be a cost effective option to upgrade to the Fuse.
Still not that bad of a deal even if you don't sell your old parts and live in a state where the Fuse isn't on the roster but are allowed to build off roster guns for personal use.

 

GuyD:

Thank you.

All four of P365 FCUs have flat triggers.

I acquired an Xmacro Comp conversion kit a few years back. I tend to not check for used parts on GB and almost never check for firearm parts on eBay.

Found a used Fuse Slide assembly on eBay. $388.30 later, the eBay Fuse slide assembly WITH TruGlow TFX Pro Sights installed arrived today. IF I could have had any sights installed that I wanted, these are the ones I would have picked. I have not fired it but I could not be happier. It may not be new but it is like new with very little wear marks.

I think I now have most of the parts to have just about any P365 version that I feel like using.

Thank you very much.

Gary

 

Glad things worked out. It is amazing how many parts are out there. I keep buying and keep building. Adult Legos sure is fun.

Happy Shooting!