Where mink urine is pretty much the only commercially available mustelid urine would it prove effective in a marten gland lure formulation? Thoughts?

All I can say is, try some and see how it works for you?

I always try to use bladder urine. When making a gland lure. It is always good to know the urine's source. Urine does not mix well with some ingredients!

For marten. You might consider adding some musk or a good sun rendered oil. Just my 2 cents.