Hi Bartmick,
I am afraid that your Red Dot sight is not allowed in 10 mtr pistol competitions. The relevant extract from the NSRA Rules is as follows:
As to whether the Brocock Aimx .177 complies with the rules, I do not know as I am not familiar with that type of pistol. However the NSRA Rules say the following:9.2.4 Sights. All front and rear sights must be strictly open; the notch must not be narrower at the top than at any other part. Aperture or peep sights or any covered, shaded or telescope sights are not permitted. Both front and rear sights may be adjustable laterally and/or vertically and may be coloured and/or include light reflecting substances.
9.2.5 Orthoptics. The use of a fixed hole or iris aperture, worn by the
shooter but not attached to the pistol, is permitted.
A short summary of the ISSF Rules:9.2.1.3 any air pistol complying with Rule 9.2.3
and 9.2.3 state
9.2.3 Air pistols used in competitions under ISSF rules may be any type of compressed air or CO2 pistol calibre 4.5
mm (.177 in) which conforms with current ISSF regulations.
Weight 1500g max
Trigger weight 500g min
Pistol must fit in a box 420mm x 200mm x 50mm
There are other regulations relating to grips and porting.
I hope that this helps.
Rutty