Affordabilty - any tacamo kit MKV MK5 MK7 MKP and the new Milsig MK3 with a base price of about 249.00
but like Arson said...theres a bunch coming out...Dye, Scarab Arms, Rap4s 468..and you'll have to get new gear such as magazines, pouches, blah blah blah
What you could do is get the MKV kit for your alpha and spend the rest of your 500 on gear and magazines...thats pretty much what i did for my MK7..box magazine and 8 magazines with 3 more on the way, magazine pouches, dump pouch...also for myself am thinking of getting the MKP tacamo kit