I would have a closer look to what kind of knives he plans to make (full tang or hidden tang, outdoor knives or kitchen knives, etc). The idea with a file guide is great, but if he only plans to make full tang knives first, he will have little use for it (OK, it can be used when grinding the bevels, but I would not advice that).
Does have have a belt grinder? A small 1x30" with a 5" disc grinder on the side can be had for under $100 and you would have some money left for a few good belts (Norton Blaze in 60 and 120 grits). Or does he plan to grind a few blades by hand? That get him material to build a filing jig like
this one.
Unless there is a well equipped workshop available any of the following items will be appreciated: Drill press, set ofg good quality files, set of Indasa Rhynowet red line sanding paper (#80, #120, #180, #240, #400, #600), Good quality vice that can rotate around 1 axis, good quality hack saw.
Of course - if he is going to be forging than there are many more items that will be needed (other will surely chime in).