It is a pretty common solution for differential armor to use the standard 8" pipe caps. Sean provided these sources:
One of the suppliers should carry it, and that is a cool idea too.
Keenan Supply - Write a review
4700 Dahlia St, Denver, CO - (303) 321-9226
Category: Pipe Cutting & Threading (Mfrs)
Website - Directions
Hd Supply Waterworks - Write a review
1910 38th St, Denver, CO - (303) 292-1112
Category: Pipe-Wholesale (whls)
Website - DirectionsPrecision Pipe - Write a review
6535 Washington St, Denver, CO - (303) 287-5138
Website - Directionsmcjunkin Corporation - Write a review
6475 E 56th Ave, Commerce City, CO - (303) 371-2540
Category: Pipe
Website - DirectionsGreat Western Pipe & Supply Co - Write a review
3860 Forest St, Denver, CO - (303) 320-4440
American Steel Pipe - Write a review
355 S Teller St # 200, Lakewood, CO - (303) 462-6715
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