Your option are quite limited to these brand. HHKB, Leopold, Topre Realforce
so it will depend on the layout that you prefer.
since your fren is helping you to get it, You should list a few models in case the shop don't have stock of what you want most.
HHKB , Leopold FC660C (Take note of the C for topre)
Realforce 87u . there are 45g + variant and 55g
Leopold FC980C, Realforce RGB , Realforce 104U