I agree that Vaseline is probably not a good option, but not with the solid at room temperature reason. Board butter is solid at room temp, and a lot of people use some variation of that.I don't think Vaseline is a good option, because it is a solid at room temperature. So, it will just sit on the surface and not really soak in.
Flaxseed oil has a very short shelf life. About a week at room temp, a month refrigerated, and a year frozen. This might not be a good option either.Do they sell linseed/flaxseed oil locally as a dietary supplement? Can also be used and not as likely to go rancid as vegetable oil.
Cutty, you might just have to bite the bullet and order some board butter (or something like it) online. The cost might seem prohibitive, but a little bit of that stuff goes a long way.