Freight is a killer. What I did was go over to Steelmet supplies and buy a length of 1" stainless rod and a can of valve lapping compound. The stainless shaft material measures exactly 1", while the cold rolled mild steel stuff is a "nominal" measurement and is oversized. Take your calipers with you.
30 mm stainless rod is also sized properly, but they didn't have any when I wanted it. For this I bought a 3 foot length of hard bar, and got Craige of AC Douglas to turn it down to size in the lathe. I'd rather give the money to a gunsmith than USPS.