I agree with YODASDAD
Based on what you have said so far....
If you existing keyboard has a MIDI out (a small round socket with lots of pins) I would recommend not getting a separate controller keyboard and use the saving to get a Focusrite Scarlett 2i4 (which has a MIDI input you can connect your existing keyboard too - assuming it has a MIDI output)
I would then consider the sE mic if you are going outside of the bundle
I would suggest calling Andertons, DV247, and Gear4Sound asking for their best price for a custom bundle of what you want
I would also personally consider dropping the reflection filter from your spec and put the saving towards an even better mic (and just use the duvet trick until you discover whether a reflection filter would help
Here are some good "first proper studio mic" options I posted from another thread
I would say the Se x1 would be considered a "good enough" mic
Essentially a large condenser mic designed for recording vocals and instruments is what you are looking for
My recommendations for good value mics between £80 - £250ish would be:
sE X1A £80
A good entry level mic if your budget is under £100
https://www.andertons.co.uk/p/X1A/condenser-mics/se-electronics-x1a-condenser-microphonesE X1T £149
This mic has a tube in it to get a classic tube tone - I got the sE 2200T, which has a tube and I love the sound of it
https://www.andertons.co.uk/p/X1T/condenser-mics/se-electronics-x1-t-large-diaphragm-tube-condenser-micsE 2200A II £179
This is a great quality mic for the money
https://www.andertons.co.uk/p/SE2200IIC/condenser-mics/se-electronics-se2200a-ii-cardioid-studio-micAston Origin £219
I am hearing some great things about these mics - they look super kewl and are British made
https://www.andertons.co.uk/p/ASTORIGIN/condenser-mics/aston-origin-cardioid-condenser-microphoneRode NT1 with shock mount and pop shield £255
I really like the "all in" design, especially the pop shield which is ingenious
https://www.andertons.co.uk/p/NT1KIT/condenser-mics/rode-nt1-in-black-w-rycote-shockmount-pop shield
When you call the stores you want to make sure you ask them to price the following bundle:
Audio interface (2i4 if you have a midi keyboard)
Mic + shock mount + pop shield (sometimes included with mic but not always so check)
STURDY mic stand - a really cheap one may start to "sag" after a while
An XLR cable
I would say this would be the perfect setup to get you going
Don't be scared to ask for a deal - and if you get a cheaper offer ask them to beat it!