I'm not familiar with this brand, so thank-you to member microcord for the information. While it's a clean build, I don't think it's a higher end frame. Outside of the fancier stay end finishing, I'm seeing only good, mid-range workmanship standards and features (i.e no reinforcing tangs on bridges, no front derailleur hanger and a mid-range BB shell generally used on non-mitred tubes). Also, the fork blade end treatment does not match stays, suggesting an off-the-shelf fork from Tange or Ishiwata and not frame builder manufacture. The workmanship is definitely lower level than the older bicycle linked in the previous post, which is even has embossed stay caps. Components on the Ebay frame are mixed but suggest very late 1980s, which is not out of context with the frame features. I'm thinking a Tange
#1 or
#2 , or possibly Ishiwata 019 or 022 tubeset. Knowing the S/N may provide a clue to the source. If member pcb is really curious, he could try requesting it from the seller.