When you have only one or two foals each year, or even less, most of the useful things such as foaling alarms that can help you are just unaffordable.
Anyway, there exists cheap and efficient products that can help you, but are quite difficult to find.
I'm myself a small breeder, and propose you products that I already use every year.
English is not my mother language but please feel free to ask any question you may have.
I will be happy to try to find a solution to your problem.
The prices on the website do for a shipping in France. Please ask for a pricing if you live somewhere else in Europe or anywhere else (martians and other aliens are informed I may have difficulties to find a shipping solution anyway).