Actually it’s just 4 47 nF capacitors, and YuSynth doesn’t say they have to be 1% tolerance, they say matched to 1%. That is, they could all be off by 5% as long as they’re all off by the same amount.
Looking at DigiKey, for mica caps at 47 nF, I see only two in stock: a 5% one at a price of $58.98, and a 1% one at $65.71. I kind of think I would not go for mica.
The only film caps at 47 nF I see that are anywhere near 1% — 3.5% and under in fact — are polypropylene. No 1% ones in stock, the 2% one (only one variety) is $3.22. Better! 3% ones are $1.15 and up.
Polyester film is 5% and upward. In quantities of 10, or in some cases quantity 1, you can get 5% or 10% polyester caps for under $0.30 each. Then you could go through them and pick out 4 that match at the 1% level. You’d be playing the odds — you can buy four 2% polypropylenes for about $12, you can get about 40 10% polyester ones for the same price, would that be enough to have 4 matched at 1%? Probably, I would guess, and then you’d have enough left over for many projects to come. But no guarantees!
Here’s an easy circuit for doing transistor matching at presumably a better level than HFE measuring: