Another vote for Tractor Supply Store for PG USP

It's not carried at all TSS, but those that do charge about $21 (plus any local tax).
I get my VG from local CVS or Rite Aid, about $5 for a 6 ounce bottle of Glycerin USP Skin Protectant, near the bandaids. Yes, it can be cheaper to
buy a full gallon online, but I'm happy to pay more and get it fresh (the stock rotates often at my local pharmacies -- maybe there are a lot of DIYers in my area

)