1) Magma-safe screwpumps, as mentioned,
2) Apparently minecarts
3) Magma-pistons (useful for one-time delivery, per instance)
4) Just put your magmaworks down at that level
I find pumpstacks awkward, haven't perfected minecarts yet (to my shame), never tried a piston method and happily do #4.
I tend to find a bit of diggable stone adjacent to a high-point of sea, within which I can dig a magmaduct (and do various things that I've explained elsewhere, but will leave out of here, for now) above which I set up my Magma Workshops and ore-stores, etc. I don't have much difficulty with this industry being up to 100Z away (I have expanded inter-cavern spaces, as well) from the surface, but then that's the way I work.
Is the monster in your fortress, or just scaring you from behind a sealed-off area?