Most of the gaskets you will need should be the same as berkeley or easilly modify. It looks like it's mixture of bayjet and berkleley parts anyhow. Appears to be Berkeley G bowl, and also looks the like the shaft and bearing cap have been exchanged with a later berkeley pieces. The original shaft and bearing cap were similar to 12JA pumps and WJ jacuzzi's. One can only theorize on impeller but I'd be willing to bet who ever did all the fancy mods replaced the impeller also.
....and i may be wrong but I believe your transom adapter is berkeley also

When you get a chance snap some underneath pics of the intake and loader area, just curious.