What evidence is telling you that you need new crank seals?
Anyway, most dealerships and average motorcycle shops won't touch these old machines for a myriad of reasons. For one, they may not have anyone with years of experience on them or they realize there are old, aged parts....nylon, plastic, rubber that might get broken just getting into preliminaries of disassembly....parts that may not longer be available....parts that they do not want to be responsible for replacing. Old tired threads in aluminum, frozen connections....more problems just not worth them dealing with and don't want to risk anymore consumer problems than they have to.
Like most successful businesses strive for, a 'keeping it simple and fast' policy is shared among motorcycle dealerships also.
Short of getting some referrals from other members here, I suppose you could wander in the back way of a service department at a Suzuki dealership near you and look for the oldest mechanic you can find back there

and see if he might be interested in doing it for you 'on the side' or maybe he will know someone that could help. Maybe even just ask at the service counter or parts department if they know of any shops that may take on the job. Check the for sale/want to buy classifieds of local and neighborhood papers for listings 'looking to buy 60's and 70's Japanese motorcycles'. These ads could be listed by old mechanics and/or motorcycle salvage yards that could help you or direct you.
Personally, I would be leery about having any work done at a 'shop' that is actually part of a salvage yard. I'd be nervous about a few parts 'switch-er-oos'
I'd say the AVERAGE hourly shop rate around here is probably $80.00 an hour. Very small, independent shops would be just a little less. I won't venture a guess on how many hours it would take a professional to do the work you want but I think you would want to call Bill Bune Enterprises in Anoka, Minnesota as far as rebuilding the crankshaft is concerned and get a labor price and maybe parts price if he has them in stock.
Many Sundial members here have shipped crankshafts to them over the years, including myself (T500) and not too long ago, they did cylinder boring for me and supplied Wiseco piston kits (they usually keep in stock) I bought from them. Along with a discounted price, it of course was convenient since they already had the kits in stock. Most shops will just farm out the crankshaft work to someone anyway, so you might as well ship it to a very reputable business like Bill Bune Enterprises.
Good Luck