Yeah mix them 50/50 you'll get a nice 0w30 about 10.85 cst or go up to 60% Mobil 1 if you want a thicker 30 grade possibly in the upper 0w30 range also, which would be about 11.33 cst.
It's possible you will end up with a 5w30 but with excellent cold flow properties regardless since it would be on the border of 0w30/5w30. Hard to tell exactly with the visc calc, but the KV100 can be determined very well with the calculator.