So far I have not come across anything that beats the big Harken auto ratchet block and the Harken swivel base. I tried the Ronstan swivel for a while and though it is a very nice piece of equipment, with more adjustment options then my trusted old Harken swivel, I did switch back to Harken. Maybe it is something personal? Perhaps the contents of your wallet and your personal preferences are a better guide here.
N.B. An auto ratchet block is a block that automatically switches to ratchet mode above a certain load. Below that load set point it is a free running block. The Harken block does it at the right load each and every time where others may have some variance in the load set point. But who am i to judge that, I don’t have a lot of experience with auto ratchet blocks from other brands. Note that most of the fleet seems to prefer the Harken auto ratchet block. There must be a reason…..
There are cheap alternatives like this one for example: http://www.sailboats.co.uk/Catalogue~Rwo_Main_Jammer_Standard_Base~p_R1950~c4621.html Since it has a sheave it would save you a block. It is minimal and I have seen them break too but it is good enough when you are on a tight budget. Though I consider a good swivel base and a good ratchet block are worth the money, there are other ways to save money besides the ‘el cheapo’ RWO jammer. Try in Google: “swivel cleat uk”. This Google search should set you on course for Harken swivel base alternatives. And do you really need that ratchet block now? Perhaps you could make due with a simple block for the time being? And finally: visit boat jumbles that many clubs have as a season opener.