I ordered a Mishimoto Intercooler and piping for my Duramax and it’s decent quality workmanship. Fit was not bad considering I went from OEM to Custom. My buddy also runs their Rad and Intercooler on his Evo, equally as nice as what I put in my truck.
I you keep your eyes peeled, there are tons of old Torch Works, Blue Torch Fab, PWR, & Toomey radiators for under $100 in awesome condition. If not, those cheap ASI ones on EBay are getting surprisingly good results.