Unfortunately, it's only been released on VHS in SLP mode. I don't know why Disney can't get its act together and release this on DVD already. They finally released A Berry Bear Christmas on DVD in the UK, and I thought a region 1 release would be a no-brainer. It would probably help if someone at Disney was managing Bear and the Muppets. After a handful of DVD reissues and Breakfast with Bear, nothing has been done with the property since the purchase.
If you can find Halloween Bear on VHS, it's worth picking up. I'd recommend checking your local listings for the month of October, but I don't think Disney Channel is even airing it anymore. With Halloween coming up, there's a chance they'll air it as a special or something.