Tripartate Sash Windows in North County Dublin?

Sleepy

We're living in a 1920's or 30's build that had it's original sash windows ripped out by the previous owner and replaced with cheap aluminium double-glazing that's at the end of it's useful life (almost every window in the house has some condensation between the panes).

The house is in an ACA (Architectural Conservation Area) so simply replacing the existing double-glazing with modern uPVC isn't an option: we're obligated (and want tbh) to return the house to how it should look.

Looking at the off-the-peg options from Munster Joinery and the like, ours seem quite different to the usual 6 over 6 arrangement (though we have one of those on the front). The upper windows, for example are a tripartate 5 over 10 arrangement. See below for an example of one of the neighbours' front facades:



Am I right in assuming I'm going to have to get these made-to-measure? I'm assuming this is *way* more expensive than standard sized since the enclosures etc. will have to be near-perfect copies of the neighbouring houses and will likely require sign-off from the local authority's architectural conservation office. The front door will have to be made too, since ours is an awful uPVC monstrosity at present.

On top of that we'd be replacing an additional 2 ground floor and 3 first floor windows and a set of French doors to the rear. I'm not sure we'll have to meet the same standards here though as only one of 6 houses on our terrace has sash windows to the rear and the rear face of the house is a 1980's/90's extension.

Anyone had this kind of work done before or in this line of work who could give me a ballpark figure for the job? Has anyone doing similar managed to get the Built Heritage Investment Scheme grant from the local council as, from my reading of it, this kind of work in an ACA should qualify?