[ShelledPants]

So I'm positive that this isn't a new idea as it's common place among WE M4 users, but it's something I would like to confirm with the real steel shooters / KSC enthusiasts out there...

Long have I heard that certain KSC guns can take certain real steel parts (the trigger in the USP, for instance). Having looked at the KSC parts diagram (albeit hand drawn...) many of the parts in the airsoft gun are appear directly modeled after the real steel P226 parts. I realize that the only real way to find out is to just order the parts and test fit each... but:

Does anyone have any experience with dropping in real pistol parts into an airsoft pistol?

Lastly, I have below a list of parts I suspect will work with little to no modification in the KSC P226. What are the legalities with ordering any of the parts on the list, with regards to customs and ITAR.
NOTE: I do not have my PAL / RPAL.

Cheers,
Tom

Parts Diagram:
From www.topgunsupply.com

34260100N	SIG Decocking Lever - P226, P228, P229 NICKEL			-	$13.95	$13.95
34221040	SIG Decocking Lever Spring					-	$3.95	$3.95
34225390	SIG Hammer Reset Spring - P225/226/228/229			-	$3.95	$3.95
34280446	SIG Hammer Strut - P226/228/229 New Style			-	$9.95	$9.95
34260250N	SIG Magazine Catch - P226, P228, P229 Nickel			-	$27.95	$27.95
34221185	SIG Magazine Catch Spring					-	$3.95	$3.95
34225220	SIG Magazine Catch Stop						-	$3.95	$3.95
34225230	SIG Magazine Catch Stop Spring					-	$3.95	$3.95
34280454	SIG Mainspring - P220/226/228/229/245 DA/SA New Style		-	$3.95	$3.95
34280445	SIG Mainspring Seat - NEW STYLE - P220, P226, P228, P229	-	$3.95	$3.95
34260120N	SIG Slide Catch Lever - P226, P228, P229 NICKEL			-	$28.95	$28.95
34260307	SIG Slide Catch Lever Spring - P225, P226, P228, P229		-	$3.95	$3.95
34260200	SIG Standard Trigger - P226, P228, P229 Black			-	$21.95	$21.95
1200489		SIG Take Down Lever - P220/225/226/228/229/245 Nickel		-	$32.95	$32.95
HO26019		Hogue Grip Screw - P226/P228/P229- STAINLESS			-	$8.50	$8.50