If you agree with the one upstairs, the Jade Buddha Temple is very famous. Pray for bodhisattva's blessing. Just make a wish to a Buddha and Bodhisattva, but every Buddha and Bodhisattva should worship. It is best to make a wish to avalokitesvara, who can help her recover soon. Then, she can give the temple some merit money to help her accumulate merit.
I think you are very Buddhist, and it is rare to be so filial to your mother. I want to introduce you to a good website: Tibet Destiny Forum.
There are many people praying for their parents in the forum. Have a look.
I hope your mother will recover soon!