400 BB build issues

well I adjusted the kickdown band took it out, had reverse, but no third at all, then once it got warm ( driving around the neighborhood) still no third and reverse started slipped and shuddering, so it looks like shes gonna be coming out.............not fun in a cramped Volare, torn down and rebuilt.... but first to test the front clutch pressure feed hole just to eliminate that, any recommendations for who to go through for parts to rebuild the trans ? I really wasn't looking to sink a ton into it, I have been planning to swap a T-56 in come tax return in January/February time frame, other wise its gonna be an automatic for a bit longer,

-Mike