The place below seems to have the cheapest crimpable rings. The prices and part numbers are below. They have a minimum order of $5 I believe or maybe a little more but you should meet that easy. You will need 2/0 rings for most car audio 0ga wire (Kicker, Knu, Streetwires, Lightning Audio and ect..). The 1/0 rings are just a tad too small for 0ga car audio wire. The copper rings a cheaper but the tinned rings will not corrode as easy and look nicer in my opinion.
Put the part number in the item description box and check the part number circle. They have other sizes of rings as well, from 18ga-4/0ga.
Waytek Wire
Part # .....
Description.........................
Price
36033 2/0 GA COPPER EYELET 1/2" STUD EA 0.5487
36032 2/0 GA COPPER EYELET 3/8" STUD EA 0.5486
36031 2/0 GA COPPER EYELET 5/16"STUD EA 0.5486
36433 2/0 GA TINNED EYELET 1/2" STUD EA 0.6971
36432 2/0 GA TINNED EYELET 3/8" STUD EA 0.6971
36431 2/0 GA TINNED EYELET 5/16"STUD EA 0.6971