UK Visa , currently in USA on valid H1B status, but I am yet to get my stamp on passport

I am H1B holder in USA , i.e, my H1B Status has been approved by USCIS,
but I am still to get the H1B stamp on my passport. For this reason, I
am going to the US Consulate in India while I am on vacation there next
year. On my way though , I would like to go to London to meet a friend
and hence would like to apply for a UK Visit visa . I intend to stay in
London for about a week and then fly to India from there.

Am I eligible to UK Visit visa since I do not have the stamp yet. I
will be getting the stamp in India before returning . I already have an
appointment in the US Embassy in Mumbai .