If your looking to build a true injection mold the size of the mold would need to be quite large for this size of a final product - your initial cost of steel would be high.
Production volumes for tool shops are light due to automotive models launches being pushed out. If your serious now would be a good time before they ramp up again and prices go up.
To get a shop to build this for you I would guess your looking at a minimum of 100k usd. The tolerances youd need would be low, but the steel for the cavity and core would be 50k easy not including labour, flow design/engineering and their profit on the tool.