Those Deuce risers should more than do the trick for you. They are 5.5" total length, to the 3 1/8" stock risers.
I have them on one of my bikes:
There are three issues:
1) You will need to run your throttle cables inside the triple tree to avoid problems at full (or near) lock handlebar turns. You don't say what bike you have, but the Interstate handlebar throttle clamp comes out the bottom more than the std/tourer, so the Interstate has a wee bit more slack, but my interstate still has the throttle cables inside the tree.
2) You will need to grind or sand the domes off the bottom of each riser to flat (as they are designed for a dimpled Harley tree). At least I think so (I can't see from your pic, but they all used to need the domes ground flat)
3) Since they are Harley risers they take SAE hardware (riser bolts) of 1/2 inch which is just a few thousandths too large to fit through the existing 10mm Valk tree riser holes. There are two ways to fix this:
a) Stick a half inch drill bit in the riser holes and shave off a few thousandths of material (minimal material is removed)). This does not damage the bike at all, and you could always go back to proper metric hardware/risers any time with no loss of strength, and no wobble (torqued down properly), or
b) Buy some of these SAE to Metric conversion bolts and then you don't need to use the drill. These are fully plug and play with the Deuce risers and the existing metric holes in the tree.
https://www.jpcycles.com/product/zz50005/baron-custom-accessories-riser-adapterNEVER FORGET TO PAD YOUR TANK for riser work, or dent your tank.
A sheepskin driver's seat cover will help, and so will an Airhawk seat cushion which are both cheaper than a new seat. Both will sit you a bit higher. Only inflate the Airhawk cushion about half or a bit less full. Completely full and you will wobble around and maybe go up on the tank in hard braking (though they do not slip on the seat) https://airhawk.net/product-category/seat-cushions/
BTW, those 3 1/2 inch risers should have bolted right up; the square riser sits on top a flat triple tree, and only the holes and bolts are round. But they would have only given you an additional 3/8" rise, and hardly with the trouble.