The flattened seatstays and indented seat tube for a short wheel base are fairly distinctive. The rear brake cable stops look fairly basic compared to the rest of the frame fixtures, but its clearly a well put-together frame. I would expect some pantographing some where if it was a Chesini, even...
The road bike in their other items is pretty cool, weirdly they call that a Muddy Fox too, even though it doesn't say it on it anywhere - definitely Araya made!
Its not quite right, is it, the other option would be for a rack, but the frame isn’t that small, and it already has eyelets at the top of the seatstays!
Same rear mech, three cage lengths by 1992, only one model though. As above the chainset (and hence BB also), front mech, freehub and cassette were different.