The GRO in the Republic appears to be years behind the NI one.
I'd be amazed if they even had a plan to put records online.
Their website is desperate, no online ordering system (if Revenue can be online, why can't they?!), the forms are designed for getting your own vital records not historical ones. They do have email but it's hard to find.
However, I did hear mutterings that the LDS are going to put them online for free - they have microfilm copies of the registers, as well as the already published indexes, up to 1958 for the Republic and up to 1922 for NI.