We are having our ceremony in a Catholic church, but I am struggling on...

If you can't find instrumentals how about contacting a local school or college and seeing if one of their students would record a cover for you? I know many very talented young people who would love to do this x

I had instrumental music played through a laptop and sound system(supplied by the venue) I found some amazing artists on YouTube. I had most songs by Daniel jang and some by a group called the piano guys.
If you can’t find someone to play a laptop is always a good back up. Good luck x

The piano guys might be suitable.

Can your priest not give you a list of singers /organists? Our priest gave us some numbers of people who were familiar with the church and hymns so we don't need to worry about getting someone to stop/play music.

I regularly play wedding ceremonies and would be able to do this for you.
www.lastminutemusicians.com/members/nicolaplayspiano