Okay - here's my recommendation for a wide range of brake spares (for road bikes and MTBs)...
I bought a Campanolo Athena groupset for my then 'best bike', back in 1999. After a few years I needed to replace the brake blocks and discovered that Campag had changed the design at some point because modern Centaur blocks don't fit (Centaur replaced Athena in the early 2000s).
I'd previously found a company named Original Brake Engineering who made good-value replacement pads for Hope disk brakes so I checked them out and found that they did road brake spares too. I managed to get some new Athena-compatible blocks from them (OBE-R50R) at a good price.
I've done thousands of miles on those blocks but noticed after my last wet hilly century ride that the front blocks were almost worn out so I've just changed them again today. I've been back on the OBE website to order some spares and found that they currently have some fantastic prices (4 pairs of blocks for £8.64!!!). You have to spend £10 to get free postage so I'm getting some more pads for my MTB Hope disk brakes while I'm at it.
(I've just posted about this company on BikeRadar so this may seem familiar to those of you who also hang about there!)
The Athena blocks were easy to fit and have been long-lasting. I found that they needed a couple of rides to 'bed-in'. The only other (minor) criticism of them is that they fade very slightly on long descents if I stay on the brakes too long. I don't consider that a major weakness because it is bad practice to do that anyway (it overheat rims and therefore tubes/tyres).
The company is called Original Brake Engineering and they sell through a website named discobrakes.com. You can use Google to find them or if you don't mind me getting a small 'finders-fee', you can just click on the link in my signature line below
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