Howdy. There are a number of choices you have here. The shifter knobs, assemblies, are all over the place. I've never looked for an Amigo, but check out B&M and Hurst to start. On the interior, there are dyes available over the counter, but I've heard of only limited success with fabrics. Vinyl is easier to dye a darker color, and with pretty good results. VHT is the brand of can sitting on my shelf. Use in well ventilated area, this is nasty stuff.
I've seen dye jobs done by professional interior guys and they look awesome, but the expense is high and my belief is the interior guys would rather recover than dye. GOOD interior guys are few and far between, and they can pretty much ask their price. Or hell, just buy some new seats.
-Kevin