I have been using for a month or so now, a very similar product to tiger thread. It is called serabraid. It is a German thread I believe. I have been ordering it from southwest sewing machines out of Houston. I think there is one other member on here that has ordered a couple rolls but I don't remember who. I ordered 2 spools at a time, 500m and they are like $50 for both. The size 1000 is comparable to tigers 1.0 mm. And they have always been very present to Deal with.
I am not affiliated with them, just giving a plug for a company that has been nice to deal with. And if more people buy from them, they will keep more in stock.