Both Digikey and Mouser are top-tier electronics supply houses, either is a good choice. I think you'll find right now that there are parts shortages of many parts, including some of the parts specified on that BOM.
For the resistors, I ended up having to substitute for these at Mouser.
594-5063JD3M010F MBA02040C3014FC100 .4watt 3.01Mohms 1%
603-MFR-12FTF52-47K MFR-12FTF52-47K 47K OHM 1/6W 1%
Also, some of the prices have really rocketed up, the thru-hole .01uf caps are 38 cents! They were much cheaper a few months ago!