Roof Rail Issues

Good evening all, I come seeking information and assistance.

I recently refitted the roof rails to my Freelander 2 and one of the rear mounting bolts sheared off. Having stripped down the mount, I removed the 'receiving bolt' (technical name unknown - 19mm low-profile hex bolt, which the roof rail mounting bolt screws into) which sits under the trim.

Several attempts to remove the sheared bolt have failed, and I have reached the point where I think the only remaining solution is to replace the 'receiving' bolt?

So, my question is in 2 parts:

Many thanks, in advance, for your time and assistance.

Ah ha...One I can help with. They are really cheap from LR and looking at my receipt I now can't remember which bit was which. I bought 2 'bolts' and 2 of the plastic bits that push into them to hold the track
I think the bolts are listed as Fasteners which are LLR001651 @£2.40 each and the plastic bits are listed as Studs @£1.16 each

That is weird...just checked the email and it is the other way round, the plastic 'Xmas tree' clip/fastener is the expensive one

The stud is the 19mm bolt - lr043910 stud £1.39 inc vat


Welcome by the way (I always forget that bit)

And...ordered!

Thanks, Leomas, really appreciate the help.