Here's the thing , and there are things .
Downer alert !!!
That machine could work for what I did on mine . It is lightweight and cheap. Minimally I'd go , um , more sterdy .
There is more , you will need a collet set and holder to hold the milling cutters , milling cutters , clamp set ,machine vice if you want to do anything else , and the obvious other bits .
You could buy a minimum OK quality machine for 2 to 3 grand with collet set and vice . Still need cutters .
Having said that , like mine it can only machine things square .
The Tuttle lug on the casting is quite good and square . It's only just oversize to a Tuttle . So a quickish , ( 15 min ) , file and I'm snug in a 16 mm Tuttle box hole . All good ! I used this to hold the fin to machine the base .
It gets way techo trying to hold the fin to mill the PB angle . Kinda can't be done because that good square clamping surface is what you want to change .
Two options , cast extra square lugs on to the base to clamp on to , or cast a PB base .
Is that an easy option ?
The good thing about your fins is , the flange surface does most of the work , not the fit in the box .
ps : the fin finish is great , just a little flapper wheel work is needed for a fresh cast version .