Rebuild 12 bolt or swap to 9 inch?

[Jackson's Dad 64 C10]

I need some advice. I’m working on a 1964 C10 with my son for him to drive when he’s 16 (he is 12 now). It is currently a bare frame, and we have just started installing a No Limit IFS, and I have No Limit goodies for the rear as well. I’m keeping the stock trailing arms, as ours are in good shape. Part of the suspension install will obviously be the rear end. The truck came with a 12 bolt truck diff, it’s open wheel with an unknown gear ration. I did a 5x5 bolt pattern on the IFS from No Limit. I’m trying to decide if I should have the 12 bolt rebuilt or swap to a 9 inch. There is a really reputable shop in Clemmons, NC who will do the rebuild and axle swap for around $2400. New gears, Eaton limited slip, etc. I’d still have to do disc brakes, which I am estimating around $500. I could also go with a complete bolt in 9 inch including brakes from Moser or Currie for not much more. I need some advice on what to do here, or if I’m missing another option to do it with a little lower impact to the budget. What say the forum? Thanks!