You can drive without an alignment, not ideal but you can. 20KM will be easy, I drove my car to work and back for a week before I could get sorted and I'll be getting a check over from John Fowler when I can too to make sure the alignment is good.

Otherwise $185 for fitting sounds alright, I did mine at home but it ended up taking me a while because I couldn't crack one of my rear bolts and rounded it, but an angle grinder fixed that.

HSD are fine, few people around here use them. American Dave is one that I know of, and myself too. I went for 7kg springs (8kg stock) to take some of the harshness out and I have no complaints. I have had one issue of the fronts adjusting themselves slowly but that is just the lock ring not being tight enough, I'll get some lock tight for that next if it still isn't tight enough.

I paid $1350 for my set so $1450 isn't too bad.