Not sure if those links answered any questions or not.
LaBelle used to make teflon coated 30rd. mags, as well as other varieties. Black or grey teflon. Sold them to other distributers with various floorplates. Bushmaster, Defense Procurement Manufacturing services, blank floorplates, maybe other variations.
The Bushmaster and Defense Procurement varients are pretty popular and go for $35-$45 NIW if you find them.
I have several black and grey teflons. The plastic wrappers on the grey Defense Procurement mags clearly say LaBelle on the bag, with a date of '87. The black ones (also Defense Procurement) are in barcoded bags similar to any NIW G.I. mags, but do not list a manufacturer. They all have black followers.
The mags with Panther floorplates are being sold by Rguns currently, as you see in the links above. The best guess is that they are Labelle mags that started life with blank floorplates. Not sure if the green followers were installed at the factory or later. At some point they have been unwrapped, new floorplates installed, and repackaged.
Their history is a little cloudy due to being altered and repackaged, so they are not commanding the higher price that the Defense Procurement marked mags bring. No manufacturer markings on the bags, so who knows for sure?
Hope this helps.