Issue with price when the product Default UoM is different from the product Purchase UoM

Here is the problem:

• We have wires in inventory that we use for production (BOM) in "Default UoM" inches
• We have the same wires that we purchase in "Purchase UoM" feet
• The wire cost price is 0.49/feet

OBSERVED RESULT:

• The Purchase Order calculate the price using the "Default UoM".
• The UoM conversion from inches to feet make the "Purchase UoM" factor at 12.000048
• We have to convert the "Cost Price" to 0.04083 (0.49 / 12 = 0.04083), this takes to much time and is confusing.
• When adding the wire to the PO we get 0.48996 instead of 0.49 because of the rounding.
  Result, NOT good because we never get the right purchase price on the purchase order.
• Also, the stock values are in inches and this is not good as well.

EXPECTED RESULT:

• That purchase price calculation ia based on the purchase unit defined in the product and that
  the supplier information does take the purchase unit into account (instead of the production unit).
• Stock values should be expressed in feet (Purchase UoM), not in inches.

Anyone found a solution ?
Thanks