This is a great find! :) I actually prefer this model to the 401 - the stitch selector knobs get gunked up and sticky pretty fast on the 401 and the 403 doesn't have this issue. :)
You can get huge sets of those "top hat" cams an attachments on eBay for pretty cheap prices if you buy the sets intended for Touch & Sews and not look only at the ones that mention 401/403 in the title. The white cams in those sets won't work, but the black top hats will and so will Touch & Sew feet and attachments. Those can sell for almost nothing, sometimes, while the ones specified for 401 or 500 models can go for crazy prices. :)