Very good point.
The Hiromotos are excellent knives, and are very keenly priced.
For me, the Yoshikane is (still) right
I would say 3 stones should give you all you need. Grits something like 300-5000, 1000-2000, 5000-6000.
If you have the budget I would
Don't forget about EE's forum discount too!
Being in Europe does change the picture a bit, but I'm sure you can get the "standard" recommended set easily enough if you look around, the
Eden 240/800 and 2000/5000 combos are inexpensive and will serve you well. Or push the boat out and get the Naniwa 800/5000. Technique is far more important