Rising prices, carpenter wants to switch from birch to pine

[anotherscroller]

Hi!
We just ordered a bookshelf to be fitted around our living room door. Paid the deposit and everything. Whole thing is costing about £7000.
Carpenter emailed yesterday saying he’s really sorry but the birch plywood they normally order to make shelves has doubled in price because of the war in Ukraine as it was produced in Russia. So they are asking if it’s ok to use pine plywood instead.
He says it’s just as durable, it’s just that you can see the wood grain through the paint and it’s not a completely smooth surface, unlike with birch.
I’m a little disappointed because I’m not a fan of pine, but it’s painted so maybe it doesn’t matter.
My husband thinks they should pay for the birch seeing as it was what was agreed.
I don’t want to kick up a fuss because the type of wood wasn’t actually specified in the purchase document (not actually signed though).
AIBU? (Or rather, am I being a pushover?)

Pine is a zillion times cheaper than birch so presumably the £7k quite has dropped significantly??

I remember having a bespoke kitchen dresser made in the mid 90s which was £5k so £7k today for what is probably quite a large piece of furniture doesn’t sound too crazy.

Sorry I was actually looking at the wrong quote — it’s £5,200. Is that better??