Hmmm. If your question is "Can this be done?", the answer is yes- I think so, anyway. But, by the time you're done, the diagram isn't going to be remotely like the SD diagram. And you'll likely need more than just a pair of switches.
The SD scheme basically works like this:
The "series junction" between the two coils of each pickup are wired to one pole of the 5-way switch; the hot wires from each pickup go to lugs 1,2 and 3 on the other pole.
The push/pull switch connects the one pole (with the series junctions connected) to ground, or not. When that pole is connected to ground via the P/P switch, you get single coils from each pickup as you move down the 5-way switch- each series junction gets grounded, thereby grounding one of the two coils at both ends, leaving the other coil as the sole one operating.
Flip the P/P down, and the series junctions aren't grounded; you then get the two coils in series, the std HB configuration.
Now, you want to add:
2) An on switch for the bridge humbucker. So that I can turn on the full bridge pickup regardless of the selector position.
This is doable with a DPDT switch, which could be another P/P pot. Your question is a bit unclear, however. Do you want the switch to turn on just the bridge HB (i.e., it overrides the 5-way), or do you want it to turn the bridge pup on in conjunction with whatever's selected on the 5-way?
Either can be done. Turning the bridge on alone is done as a "solo override"- just the push of a pot and you're there. Adding the bridge in with the 5-way is done to give you N + Br and N + M + Br.
But when you say that you also want:
1) A switch that takes it from Serial to Parallel
now you've raised the complexity stakes considerably.
To paraphrase Bil Clinton, it depends on what your definition of "it" is. . .
If you mean "I want one switch that changes all three pickups from being connected in parallel to being connected in series", then you're going to need a pretty fancy switch. And it's going to mean that the existing coil-cut scheme of the SD diagram will need to be substantially re-thought. And when you're done, "it" won't be anything like the SD scheme.
I believe a 4-pole switch will be needed to switch all three pickups into series at once- one pole to chose the series chain or the standard 5-way, and then a pole for each of the pickups- each pickup has to have its ground connection switched to make or unmake the series chain of all 3 pickups. These are not common, but do exist- not as a push/pull, though. But I'm still not sure how that all would work with your SD 5-way coil-cutting set-up- the series setting would have to override the 5-way entirely, I would think.
Not sure on this, really, without looking at it some more. I'll let others chime in here- and hope that they do so!