As for someone living in the EU (Netherlands) i'm not using Stannol anymore, because I bought a few years ago from stores through Ebay some factoryfresh spools of Kester 44 RA 63/37 3,3% core66 in the sizes of 0,80mm (ThruHole) and 0,50mm/0,40mm (SMD). Much, much better solder than Stannol HS10/HF32 I used before.
If I must buy again, I will get the same Kester 44 or Kester 285 (RMA) even if it's more expensive than the local Stannol stuff. It's such a joy to work with....
The Kester products you mention are wonderful to work with IME, as are Alpha Metals' products (
very competitive on price here in the US), as are Indium and MG Chemicals' products.
My favorite is definitely Kester though (flux products as well; 1544 & 186-18 RA & RMA respectively, and 951 no-clean). Best yet, it's readily available here and it's well priced as well.
In the case of flux however, MG Chemicals 835 (RA) is sold in hobbyist friendly sizes (100ml & 1L vs. Kester only comes in 1gal or larger or expensive disposable pens
). There are eBay sellers who break down bottles of Kester however, and I've found a seller that I'm satisfied with (product seems genuine IME).
Sadly, that's not the case in the EU as I understand it (63/37 seems a LOT harder to find in the EU, let alone at a reasonable price based on what I've seen). Based on what I've seen, 60/40 is FAR more available in the EU/UK market. At least MG Chemicals' 835 is available there as well.