I hired a crane from a local motorfactors for about £24 a week.
Something like VHS or machine-mart could supply one.
Unless you do it yourself its going to cost a fair amount.
Labour it'll be about two days work
1 Day to remove engine. Couple of hours to fit new clutch and retime new engine
1 Days to replace engine and put new fluids in etc.
It took myself 3 days to do engine removal and refit on my parents drive.
I was getting fairly sick of it by day three though. But once fired up and knowing you saved another alfa from certain doom its quite an acheivement.
I did it on the cheap. The engine cost me £220. Fluids cost another 70. I reused my old cambelt and water pump (Only had 9000 miles on it)
I then kepts the old engine for spares like sensors. Re-used my clutch as it was fine inc bearing even after 112k.
Sold the cylinder head and other parts made some money back.
In all it cost me £180 to do the swap if I inc fuel for getting the engine and crane hire. But 3 days of my own graft and maybe a few items of clothing that needed replacing.
other than that I think you'll be into the £1000's for someone else to do it.
New Clutch £170
Cambelt Kit and water pump £130
Used engine £2-300
Alfa 166 2.0 Twinnie - LPG and a few trick performance parts