Does yours have an adjustable lens? Mine is the "non Super" so the lens is fixed in focus, f-stop and speed. Mine looks to be f8 or f11. Do you have some 620 take-up spools? Re-spooling is not too difficult. Half-way through, be careful removing the tape so you don't bend the film, then re-position the tape so the film lies flat again and continue spooling.
Re-spooling is not too bad. I think Donald would agree that it is easier than re-loading 16mm cassettes.
Yep, I'll agree -- reloading Minolta 16 cassettes isn't
hard, it's just a matter of being able to roll a narrow strip tightly enough to go into the supply chamber. Once you get the strip in, with the head in the slot, and the cover on, you can turn on the lights and finish the job with ease.
Respooling to 620 is still easier, though it does require some planning ahead ("How many rolls am I likely to want?" before you leave your darkroom behind). It's easiest if you spool from 120 to 620 in the forward direction, then 620 to 620 in reverse; that way, the film will already be adjusted to the smaller core diameter and you usually won't have to untape and retape the head end of the film.
Easier still, if you have a camera you're more interested in shooting than reloading, is to find a way to use 120 supply spools. With my Reflex II, I can trim the 120 flange flush with the paper (takes about a minute, because I always carry a nail clipper) and it fits; if I do a really smooth job trimming, I can even use the trimmed spool for takeup. My Brownie Hawkeyes have the little "ears" as well as being a little tight for length; I can make a 120 spool work, but the cameras like it better if I respool. All four of my Duaflexes (one of each model, even numbered ones with the focusing, 3-aperture Kodar) will require respooling, but if there's one I shoot regularly, I'll remove the supply caddy so 120 will just drop in. I don't recall which class my Brownie Bullseye is in. I should probably finish the roll (that's been in it for fifteen years) and check.
I think that covers all my 620 cameras...
And then there's 127. I'd love to support Rera (one B&W and one color emulsion, Rerapan and Rerachrome, fresh ISO 100 film native in 127) but there's only one or two sellers in the USA and none of my 127 cameras are particularly good ones; I just cut down 120, any emulsion I want, and get a two-roll strip to fit my Minolta 16 format cameras as a bonus.