What is this UPVC part called?

[r_c]

One of the Georgian bars on the window of our UPVC door came off. The bar is held in place with these two white fixings (?) that the bar clips into.

Could you tell me what they are called and where I might be able to get hold of a couple?

[GALLERY=media, 100937]20180106_171406 by r_c posted 6 Jan 2018 at 5:19 PM[/GALLERY]

 

[crank39]

http://geofast.co.uk/traditional-range/

click the download brochure or the price list, think their about 15p each, hopefull theyll sell you a handfull but generally you buy these in the 100's

It would work out cheaper if you did away with the clips and just used a 3mm double sided glazing tape