I ship MTS by USPS Flat rate. Lg box. I was ave. 28#s of dirt in that box. Gravel of course will wt. per cu. in. I doubt you'll find a cheaper rate. You can ship up to 80#s? for the flat rate.
I don't know how many Cu In 35#s of gravel is. But I tend to think one Lg box might work. If not Med. box is $11. The boxes are free so go get a few and see how much you can load in one. Do use plenty of tape.
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