WTB - Big Block, LWP - PS Pulley - Bolt on with keyway

[mole2000]

I need the last piece for my PS addition to my 1970 C10 with a BB. It didn't have PS before so I'm not exactly sure what I need. I used the March PS brackets and a early Saginaw PS Pump. The sun went down before I could get a picture with the bracket installed, but here is the engine as it was.

March Performace lists a replacement for OEM 3770509CE. I presume that could be the part I need. I really didn't want the look of the billet piece March offers for sale.

Could this Goodmark part be what i need? I'd still like to buy something used to lower the costs...
The Goodmark part is 4044-288-655

Thanks.