Presuming you want this for MFT cloning, not hinge drilling...?
~sorry if that's wrong, but -
Wealden 2-flute spinny-thingsT1120M / 20.0 (25/32) 25mm bit height /8mm shank /38mm insertion / £15.50
8mm shank
A range of straight cutters in 8mm shank. These general purpose cutters are suitable for grooving, dadoing, rabbeting etc. ... All sizes are suitable for plunge cutting, with sizes above 9mm diameter having an additional centre carbide tip to ensure a faster and cleaner cut when plunging...
The T1420M, 1/2" is £20.10. (I've ordered the 8mm for the OF1010.)