Crisp sounding tubes for Modwright 5400ES

I recently upgraded from a Modwright 9100ES to a Modwright 5400ES. While there were improvements, the richer mid-range and more powerful bottom end of the 5400ES tipped my previously balanced sounding system into one sounding a bit overly polite with a lack if crispness in the top end.
Can anyone advise me on what tubes (output & rectifier) and power cables to chose so as to brighten the top-end.
Grateful for your advise.
I will be getting this tube this week and report back on how it sounds in the Modright Oppo 95.
The tube has open up a bit at the 30 hour mark and I'm amazed that a 5AR4 can make such a dramatic difference over a Mullard which has more body but I don't mind trading body for more detail.

This 5AR4 swop is more noticeable than swopping a Sylvania "W", Chrome Dome or Ken Rad VT-231 6SN7, you'll hear the change upon install...
Many thanks Wig for this; it sounds like the Create 5AR4 is just the ticket for me, as what I want is to trade some mid-range richness for some more crispness at the top end. Can I ask where did you got this tube? I also agree with you that swopping the rectifier tube can make more difference than the output tubes. It definitely was the case in my rig when the Mullard went in!
Thanks also to Brownsfan & the other guys for the benefit of your insights. I swopped out my Mullard for my stock rectifer tube, a Ruby 5AR4, which helped to restore some of the top/mid balance to my system. Can't wait to try the Create!
Many thank to Brownsfan and others for their knowledge and on a great find with this tube.

If you do a search under 5AR4, the name FORK will come up and you can send him a private message since he has tubes for sale on A'Gon.
Thought you might be interested to know that after I swopped out my Mullard 5AR4 for the stock Ruby rectifier which my Modwright was supplied with, the frequency balance in my system returned. I then bought a Create 5AR4 (living in Hong Kong, I got it direct from China). From new, I was a bit surprised to hear hardly any difference between the Ruby and the Create. If anything, the Create was a little softer and the Ruby a bit more dynamic. But upon swopping the two to compare, I noticed they look very similar. Further examination confirms it, the base was identical, in colour, material and moulding. And the parts inside the tube also are effectively identical, apart from minor differences due probably to the fact that they are hand assembled? I probably should clarify that I am not saying that Ruby and Create are identical tubes. All I am saying is the two look very similar to each other. Maybe the factory that makes Ruby 5AR4s makes tubes for Create too? I will put some hours on the Create and do another comparison with the Ruby and keep you posted.