That’s almost the same as the price of a new Pixel 7a, that repair quote is a complete joke. As Extras said, you could try to find a Pixel 6 on Ebay that is in bad shape (cracked screen etc… but works) for cheap and then use its motherboard. Otherwise, you could also just go for a used or refurbished Pixel 6, I found this one at €275 on Ebay: www.ebay.com/itm/186093640631 (I’d probably try to haggle a bit for a lower price).