You might have to stay with the RWS bullet. It's a somewhat unusual design, in that it has a copper-plated steel jacket and two cores of different hardness. The Accubond will have very different friction properties, which will affect regulation.

You might have better luck with Woodleigh solids, Degol Steel Jacket softs or something like that, which have at least the same type jacket.

RWS ammo uses RWS primers, the closest equivalent in character (if you cannot get them) would be the Winchester primers.

Powder used in RWS ammo is Rottweil - Norma powders and the Alliant reloader series are of the same kin (all made by BOFOR, Sweden).

Generally speaking, I have experienced RWS ammo to be from 30 to 150 f/s below stated speed.