CREATE AMAZON 'PARENT/CHILD' RELATIONSHIP TEMPLATE OR PAGE

We've been selling on Amazon for about a year with 15 or so products. We recently were suspended for slow delivery for two of those items. (now re-instated). We've fixed the one, but need some custom page work to fix the other. The problem is our "Custom-Cut " soundproofing door sweep, a metal strip and rubber loop that fits across the bottom edge of the door, preventing sound (And drafts) from coming through that gap. Very effective. But many doors are not the standard 36" width (That one's not the problem). The problem is the ones we sell that we cut to fit to the measurements of the customers door(s) which may vary greatly. After purchase, he must give us the measurement. In some cases he's late or does give it, necessitating a shipping delay or worse a cancellation with Amazon, this caused our suspension recently by being late in the customer getting his order. So now we don't offer the "Custom Cut" ones. The solution is the customer must somehow give us that measurement on the listing page before he can actually place the order. Complication is that the cost of the item goes up the wider the doorsweep, starting at about $26.40 (23") to over $50 for the 49" wide ones. Or, we create a single page with a myiad of doorsweep measurements for him to select from with prices all with their own UPC codes. Sometime they want to do more than one door.... and will want several with different measurements.