I'm not sure it's all that small, is it? It's a 1998 Stumpy and they came in sizes 15, 17, 19, 21. This one looks too big to be a 15, so I think it must be a 17.
Very nice-looking bike I agree and the last year they made steel ones, but I'm not sure it was quite the same quality as the earlier Tange Prestige frames. I don't know what Ritchey Logic Pro Nitanium means, but I'm not sure whether it was a heat-treated tubeset like Prestige. I think by this time the classic steel Stumpjumper was a UK-only model, as there was no longer any demand for steel in the US.