Aircraft fittings, AN fittings, braided hose and fittings.
All of the race shops carry them; shop around. JEGS seems to have the best prices. They are expensive. (You're looking at about $60-70 for the fittings on RB's, not counting the foot of hose.) You can get them in various colors - the traditional red/blue, black, stainless or clear anodized, sometimes in fancy anodized colors.
I have a sketch of a less expensive bypass, but it's meant for emergency use and probably isn't quite pretty enough for everyday use. In short:
- Two right-angle AN fittings, sized to match your oil cooler line size (-AN10 or -AN12, most likely). The second fitting on each should be NPT 1/2 or 3/4.
- Two NPT female unions to match the above size. You can use hardware-store iron or more expensive AN parts.
- Iron pipe, length to suit the spread of your cooler fittings, threaded both ends.
Assemble the whole thing and you have a bypass just like RB's, not as pretty but for about $40 in parts total. I plan to slip a length of heat-shrink tubing over the whole thing and shrink it on to provide abrasion resistance at least halfway over the unions.
Two AN caps to cap off your cooler neatly, a matching AN wrench, a couple of big wire ties to secure the bypass in place, and you have a busted
oil cooler fix-it kit.