Are there any negatives to just using an older water pump? The cast iron ones are fairly reasonable in price. Is it just the timing marks that are the issue?
with the 360 timing cover you won't be able to see the timing marks-- or just barely, if you can. it also exits on the DS.
the key is that it all has to work as a system, otherwise you wind up with a kludged together mess.
if i was in your position i'd look at something 70+ so it's pass side pump & radiator, and the upper will be skewed toward the DS so there's no interference with the fan. sourcing a shroud and clutch fan (or electric fan) would be cheaper and easier with that type of radiator.