Replacements for 'R-series' fuel pumps, from Mike Mudd: My Avanti came with a modified M6270 Carter pump, when I bought it. Summit still has them, for $77.95. That's a satin finish, strip pump for small Chrysler engines. It has three valves, and 1/4" NPT ports in and out. (An 'R' pump has two valves, and is 1/4" in and 1/8" out). The diaphragm isn't as big around as an 'R' pump, and the valves are a little smaller. It's supposed to flow 120 gph @ 7.5 psi. To use it on a Stude, the pump has to be taken apart, and the operating arm heated and bent. After the final heating, I think you should cool it quickly, for hardness. I posted a diagram of the stock and modified arms, that I traced, on the Yahoo Avanti chat group. Any of the small block Chrysler pumps should convert the same. If it's for an 'R2' you also need to drill and tap the boss for the boost reference line, and plug the atmospheric vent. That's easy. Mike Mudd (See pic below for original drawing.) Note from Mike concerning drawing scale: 'It's a tracing of the edge of modified and stock Chrysler fuel pump operating arms; done on 1/4" graph paper. It shouldn't be hard to count squares and redraw it on a blank sheet of graph paper, if it's hard to print exactly the right size.'