After a bit of thought I ended up with a pair of Elinchrom BXri 500 (instead of the older Bowens 500 and 250ws that I posted about a couple of weeks ago). I am starting to inform myself about possibilities of on-location opportunities, thus battery packs. I have found one that looks promising - Tronix Explorer XTSE. It is relatively inexpensive and seems on spec like a good option for me (it says it can shoot the two strobes at full power for about 500-550 pictures if you do not use the modelling light, and that will be good enough for my use).
Has anyone used them and can you share your experiences?