Gloucester_FastFreight_Bogies_OO_sideframes

This is a sprue of 8 bogie sideframes scaled at 4mm:1ft, intended for use on bogie etches for wagons such as the Lima UKF fertilizer pallet vans. The prototypes are known as Gloucester Fastfreight bogies, and had a 2m wheelbase.
It is a direct 2x scale-up of the sideframe from the 2mm:1ft bogie units I have uploaded before.
The thickness of each sideframe is approximately 2.5mm. 
Design modification suggestions may be entertained, subject to credibility, utility and effort.
A sprue of 8 should provide for 4 bogies, which is 2 wagons. Please let me know if a different sprue size would suit you, but bear in mind that below a certain size the price may be the minimum Shapeways will charge for a single model, and not be any cheaper than having a few spares.   
Detail will be rendered best in Smoothest fine detail plastic, but smooth fine detail plastic should be almost as good.  Looks like the price will be around £11.50 or £8.50 (zero markup) so there's not much if anything to be saved by having enough for only one wagon, or indeed making the detail less delicate so that they can be printed in the slightly cheaper natural versatile plastics.
For sale when I have had feedback from the potential first customer.
If you would prefer them made of something like white metal for the extra weight, I believe a company called Appleby make them, and they seem to be well regarded.
Offering for sale from 2022-11-10 in response to an enquiry - no one has ever tried them before,  so I suggest not buying loads at once in case there’s a problem!
The feedback from the first purchase was positive (hence the photo) and more were ordered.
UPDATE 2023-03-22 I ordered a set in one of the new fine detail plastics - Grey. It is more economicsl but loses a little sharpness. The new Clear fine detail was better when I tried it out for a different model, and shares the advantage of no possibility of localised support wax texture changes.