if your d3 levels are that low, you probably want to take a serious look at co-factors. if you take d3 alone, you can exacerbate possible deficiencies of d3 cofactors. you may have a few things to work on in addition to d3.. you think there's any chance you can get some other bloodwork done?
also, best to test drive a tanning bed before committing to purchase. back before i understood nutrition i had a WICKED allergic reaction to 30 mins in a tanning bed :S crazy.