Hi - welcome to the GMB. I would have thought that if these were lead crystal then it would say as much on the box - the absence of such wording probably implies these are not lead glass, though it seems a tad surprising since R.B. are well know for making high quality glass, usually. If you flick the glass, is there a good 'ring'?
Rather than lead crystal, it's usually o.k. to say simply lead glass - it means that during the melting process a quantity of lead oxide is added to the batch - this makes the glass heavier, better suited to the cutting process, and helps to produce that long lead glass ring when the glass is flicked. Such glass is mostly more expensive than non lead glass, and the added lead usually gives a better colour to the glass.
In the U.K., full lead glass/crystal, is supposed to contain c. 34% of lead - in other countries this percentage varies, and can in some cases be a lot lower.
The crystal bit is really just a description of the obvious - that the glass is clear.
Modern cut brandy balloons such as these, have little significant value - though of course it depends on your interpretation of 'significant'. Have a look on ebay or other on line auction sites - you will probably get an idea as to approximate worth by looking at similar glasses.
Not entirely sure of your meaning of "Is any of the other glass lead crystal?" - assume you are speaking only of these Braemar glasses?
You might try the Replacements.com internet site - look under Royal Brierley - you should find Braemar.
sorry if this not exactly what you wanted, but as mentioned, don't think these are going to pay you a fortune. Let's see what others here think.
just looked, and 12 oz. Braemar brandy balloon is shown on the Replacements.com site, but any prices shown will be for new replacements, and will be way more than the second hand value.