Lurch Knight:
That is Paul Casey's(KRO:tigersharka) KITT on eBay he runs the Vegas KR Festival's and it's been on eBay for awhile
You CAN build a replica from any 82-92 firebird ,But some will require more work/$$$ then others like removing fenders,Ground Efx,Rear bumper,taillights....ETC which can cost some $$$$.
Also people have different taste lol. Do you want a 100% authenticic KITT/KARR replica or KITT/KARR inspired replica ??
And as the years go by and now hit the 30 year mark,Original 82-84 parts like Fenders,PMD seats,Taillights,Turbo Cast wheels are going to get more harder to find and prices will go up as with any H.T.F muscle car part

. You don't wanna know how much 15" Turbo Cast and PMD seats are going for
I won't even get into the KR conversion parts side,Seems like allot of parts are taking 1-3 years from order to delivery and vendors are coming and going these days
My BEST advice is to get a clean 1982-1984 trans am,SAVE allot of $$$, grab a 12 pack,and get ready to wait
Dave