probably not.
the GB mounted coast guards, or riding officers, like their american counterparts were formed to guard the coast against smuggling from the continent, life saving was added as a duty later. in the USA it was the 'revenue cutter service'. the british had a mounted section. as did the USA, the british one was recommended for disbandment in in 1783, but became the UK coast guard formed in 1822 from a merger of the Revenue Cruisers, the Riding Officers and the Preventative Water Guard. there were at their peak only 291 riding officers to guard the whole UK.
the american one finished their last mounted patrols in 1944, returning 3000 horses to the army, after the threat from the japanese and german navies landing troops or spies subsided. the US Coast guard remains one of the american military forces, as well as a federal law enforcement agency. the UK version is unarmed, not military and not a law enforcement agency.
the riding officers carried a cutlass and a carbine and supplied their own horses.
the fensibles also had an american counterpart, they were an early naval reserve and they were probably the (UK & USA) smugglers the coast guard was on the look out for. they were formed from the local port's fishermen, and sailors. a kind of local naval militia.
one of the USCG's mounted troops of the beach patrol. note the saddle mounted rifles, no sabres, and each had a dog. i see dobermans, german shepherds, boxers.

they also could carry submachine guns, pistols and a 43 lb. 'portable' radio for comms.