just make sure it is the N5, TO-220 version. The TO-92 won't stand the heat. However, since the N5 is only needed for the 'top' MOSFET, you can split between the N3 for the 'bottom' of the cascode, and use the heatsinked( and more expensive ) N5 on 'top'.As I could use some of the N3's ( and Mouser stopped stocking them ), thanks for the notice on that source. If they are seling the N5 for 66-cents, I will buy a *BIG* sack of them....
regards,
Douglas