Expendable Foci, Overpriced? Options

[Moonstone Spider]

I was looking at the price of expendable spell foci when building a character recently. It struck me that the Foci was way out of bounds in price relative to it's usefulness. Instead of buying a single extra die, for a single spell, I could get:

An ingram valiant. Sure Mages can cast combat spells but dishing out a serious 10 round burst from one of those and doing 17D damage is worth a lot more than an extra die on one combat spell that's gone forever afterwards.

OR

Lvl 6 fire resistance, insulation, or shock resistance for my armor (Actually this is an understatement as those cost a lot less but we're talking a starting player).

OR

Enough IPE grenades to take out a Dragon (Okay, not a dragon but at least a HTR team).

OR

If you want to go magical, 3 additional force points on your shamanic lodge or a rating 4 hermetic circle for each type of elemental.

I think the expendable foci is overpriced compared to the other gear you could get, it's just a single die after all. I'd see it's price as more reasonable if it were 50-100 nuyen per point of force, possibly on a curved scale to make the really high-end foci more expensive per point.