Dear all,
Thank you so much for your replies.
I am so glad I asked this original question as it has really helped me consider all the options and I've made a decision.
My existing Helios Naturesport 10x50 WA binoculars have served me well and until I dropped them they were fine. FLO recommended Action Optics. I got in touch with Richard and he says he can repair them. Those binoculars are now in the post. This makes economical sense as it will be cheaper to repair than buy new. These binoculars are good for general day to day usage and also viewing the night skies.
(Thank you, David, for your suggestion. I did try taking them apart and I can see the prism and the bracket but I wanted to entrust them to an expert, hopefully Richard at AO can fix them)
This process has also convinced me I would like a pair of 15x70's for additional cosmic-viewing options. Thank you Stormbringer and Bosun for recommending the Helios Apollo's. I searched FLO's website and lo-and-behold, there were a pair of second hand Helios Apollo High Resolution 70mm Binoculars 15x70. They are very highly rated, including on BinocularSky. What a deal. So I have bought them!
(Thank you, Alan, for the link. I couldn't see what it linked to as I don't have permission, but, I am sure I am going to be pleased with the Apollo's)
So, if this all works out as planned, I'll get my old bins fixed and an exceptional pair of new bins for less than my original budget to replace a set of bins that I only had to replace because I dropped them in the first place!
Thank you for your help everybody!
p.s. and, if i do need a set of new 10x50 bins in the future, I know that the Nikon's are the ones to go for.