To @koxing
You said:"There are also battalion level components such as fire control centre, reconnaissance, weather, etc."
I suspect that all this is critical for the use of unguided missiles (for which it was originally designed, hence the roots of batch loading and so on).
But for guided missiles it will probably be all right without these components, the targets' coordinates will be provided by regular SAM reconnaissance, the missile in flight kind of does not exchange data with the ground, only with the satellite.
You said:"Then 2 questions: Why 50? Why not 100?"
The figure is from a street lamp, and of course it will vary many times, depending on the desire to use one or another power. I was referring to the subjective feeling that industry could literally flood the army with such (or simplified, but with sufficient functionality) machines if they wanted to.
You said:
"Do you know what the cost of the HIMARS is?"
Cost is an elastic term, the price for the customer is based on repelling R&D, so there are millions out there. But if it really comes down to it, a world war of attrition and mass production, the cost of materials and labour should rather be taken into account.