Should it be possible to source similar bricks?

[catinapickle]

We have a builder doing some maintenance jobs on the house we've just bought. There are 3 bricks missing at the top of the dividing wall between our house and next door - see photo. We agreed that he would repair it, but the bricks he is intending to use don't match. Although they are the right colour, they are about 1cm shorter and the other dimensions are also about 0.5cm less. He thinks they will be fine "when they're mucked in" but I'm not convinced.

The bricks we need are approximately 22.5cm long with a cross section that is 10.5 x 6.5cm. We thought they might be "London Stock" but we've checked the dimensions of those online and they're a bit bigger.

Is it reasonable to think we might find the right type with a bit of effort? Anyone know what they're called?

You are looking for Imperial sized bricks. They are still made but not as common as metric bricks (what your builder is suggesting) and more expensive. However as you only need 3, I would look online and find a supplier. They probably won't want to sell you only 3 but would probably send you a free sample brick. Find 2 friends to ask for their own free samples to match yours and you're sorted. Or ask them to send you 3 samples of similar colours for you to 'pick' the best match, if they're close enough you could probably use all three for your wall.