Radiator cap replacement for non stock aluminum radiator

Not real happy with the shorter tangs on the replacement I found. So I cut the old cap out of the billet housing. Compared photos online and it's a Stant piece rated at 16lbs and has J8 stamped into it. No part number. These things do not appear to be available retail.. but it sure looks like everyone making a billet or custom 16lb radiator cap has access to them. Checked all part numbers starting with "R" and the closest I could come is the R31 hex top that seems to be discontinued. Not looking to spend a lot of money on a custom cap just so I can peel the Stant out of it.

Just in case anyone ever runs into the same situation... the Stant cap you need can be found hiding under the plastic on these. The top photo cap runs about $6... so naturally they are out of stock everywhere. The bottom cap runs $15 and is in stock... extra $10 for a sticker I'm going to remove... lol.

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