I don't know if it is still available but I've used Tom Langdon's mini HEI distributor (along with the square coil he sold with it) and have been happy. In fact there has only been one small problem...one of the cups that fit inside the molded plugs on the distributor cap came loose and I had to use a bit of epoxy on the bottom of the brass cup to keep it in place. Not Tom's problem at all. Took a few cents worth of product and a day for the J-B Weld to set up fully.
I do have a foreign made HEI distributor here that I converted to work on a 235 (easy conversion). I am not entirely certain where it was made...part of me suspects China but also possibly Brazil, Mexico or elsewhere in South America. Only two problems: While the engine is running, oil will wick its way up the rotating shaft and spill into the distributor (and from there eventually leak out the bottom of the cap where it connects to the distributor) and the cap is larger than I like (the coil is part of the cap). I suspect I could rig up an o-ring or something else to keep the oil from traveling up the shaft but I haven't messed with it. It could be that a rotating seal was meant to be at the top (so the shaft would be oiled) and was forgotten at time of assembly. But I will say when I used it, it operated as it should and had a good vacuum advance and mechanical advance. It was originally meant to be used on a 230 or 250 engine and I bought it around 1996-97. As I recall (and I'm working from distant memory) the connections on the dist cap were "outies" rather than "innies" (meaning old style plug wires worked with it).
