Broken Combi

Our combi has been broken since Wednesday, the maintenance chaps are not to blame. It has been an intermittent fault so very difficult to diagnose the problem. Anyway to come to the point, years ago we had a "Baby Berco" boiler,I think that was its name. Are there any such available today? I thought that perhaps I would get one so that we would at least have a reasonable supply of hot water if it happens again. I remember that during the very cold Winter in the 60s everyone lost their source of hot water in the RAF married quarters, where I was living, as the boilers had all burst their water jackets. Then we had a "Baby Berco" which earned its weight in gold, well at the gold prices those days!