Filling Oxygen Bottles in Seattle Area?

After the recent extended thread on supplemental O2 use, I opted for Darwin Barrie's suggestion, and rolled my own at very reasonable cost. But now the challenge: where to get that new D size cylinder filled? The welding supply shops don't want to deal with it and/or need 2 weeks, and the medical supply folks seem to use the exchange bottle system and are wary of some guy just wanting to fill his own.

The FBO at Bremerton, my home field, does not fill oxygen bottles.

Short of heading off to some place like Boeing Field, or buying a transfiller setup and renting a big tank from the welding supply shop, does anyone have any tips for where to get this filled easily, at reasonable cost?

Thanks for the tip, Carl. I stopped in a Regal for some pilot supplies last winter when the RV was being painted next door at Sunquest, so I know where they are.

Also, per Airnav two of the FBOs at Olympia (KOLM) appear to have O2 service, so I may give them a call too and see what they offer.

Fortunately, this is not the kind of thing I would need to refill on a frequent basis. If I do have that need, it will only be because I am getting to do LOTS of XC flying across the mountains. . . .in which case I can live with the inconvenience