"...a mint rare version like the M1 Tanker Version..." No such thing, except for about 9 experimental rifles. There are no real 'Tanker' Garands. Any you see are bubba'd rifles.
"...Springfield M1 Garand..." There are M1 Rifles made by Springfield Armory Inc.(same U.S. Co. that makes the M1A) and M1's made at the Springfield Armory. They're not the same.
SA Inc. rifles use cast receivers(as opposed to forged) and are commercial copies. They have no collector value. Nor are they made any longer. MSRP was around $1000US. If you find one, it'll be way over priced.
Springfield Armory(closed long ago) made rifles are milsurps. As with all milsurps, the price will vary according to condition. Rarity of the maker enters into it too. Epp's recently sold one(no manufacturer mentioned), in 'fair' condition, for $699.
There are lot of gun show sellers who think an M1 in any condition is worth the same as one in better condition. I've seen 'em, at gun shows in poor condition, with near $800 price tags. The guy carried it back and forth a lot.
For a milsurp, in decent condition, expect to pay closer to a grand, retail.