The therapeutic benefits of massage are well established, and include reduction in blood pressure.
This study compares having a back massage with simply lying prone for the same length of time. It concludes there is no significantly greater benefit on systolic blood pressure from massage than just lying prone, at least for women (the study had only female participants).
So, if your main driver for a massage is to help manage your BP, try lying face down for at least 15 minutes instead, and see how that helps. Of course you miss out on the sheer pleasure of a massage, but lying prone is free and available in the comfort of your own home at your convenience.