A QUICK glance at Moet and Chandon's New York chart might make the territory's big spenders feel a bit jealous because these same luxury items, amid continued low US inflation, are becoming increasingly affordable to the American consumer. According to the New York report, the Moet Luxury Index, which remained essentially the same as last year at 1.83 per cent, was complemented by the Consumer Price Index which decreased slightly to 2.9 per cent, down from 3.1 per cent in 1991. The continued low inflation rate for Moet's Luxury Index - tracking the cost of a dozen luxury goods and services in New York since 1984 - is making many of life's luxuries more accessible. ''In the world economic environment, sellers of luxury products in the American market want to increase sales,'' said Mr Fred Alger of Fred Alger Management, a New York financial consultancy. Prices for eight of the 12 items tracked by the index showed no increase in 1992. Of those items that did go up, the most dramatic increases were in the costs of a Rolls-Royce Corniche IV Convertible at 10.7 per cent, and ticket to the Broadway show Cats, at 8.3 per cent. But, in order to put all prices for luxury spending in perspective, Moet and Chandon also took a look at prices the elite paid for such ''essentials'' in Paris in 1748 - and for today's big spenders, the results are hard to swallow. That year, a ticket to the ''Theatre du Palais Royal'' was about 80 cents, a bottle of fine champagne was less than US$1.50, a gold watch went for about $54 and maid service was just under 26 cents per day.