Q: What's the value of my 1953 or '54 Les Paul model Goldtop Gibson electric guitar with its case? My late-husband added a "Bigsby" tailpiece to it around 1955.
A: Your Les Paul guitar is worth around $2,500 to $3,000, depending on condition, said vintage musical instrument dealer Frederick Oster, 1529 Pine St., Philadelphia, Pa. 19102, (215) 545-1100. The replaced tailpiece reduces its value, according to Mr. Oster; with its original trapeze tailpiece it could fetch up to $4,500. The serial number on the back of the guitar's head will help date it.
Gibson Guitar Corp., of Nashville, Tenn., still produces over 40 different models named for famed musician Les Paul, who popularized electric guitars. Its least expensive Les Paul model starts at $899. A reissue of the 1956 Goldtop, which resembles yours except for the tailpiece, lists for $2,549.
Many vintage guitar enthusiasts read 20th Century Guitar, a bimonthly magazine which also lists prices and shows. Annual subscriptions cost $18 from 20th Century Guitar, 135 Oser Ave., Hauppauge, N.Y. 11788, (516) 273-1674.
Q: How much is my foot-high, blue-and-white, floral Chinese vase with elephant handles worth? The Montreal dealer from whom it was purchased said its double-diamond-shaped base was unusual.
A: Your Chinese "double-lozenge" shape vase with under-glaze blue decoration dates from the 19th century and was made specifically for export. Since these export wares aren't widely sought after by Chinese porcelain collectors, their value largely is decorative, observed Oriental art dealer James Lally of J. J. Lally & Co., 41 East 57 St., New York, N.Y., (212) 371-3380. Assuming it's in good condition, your vase could retail for around $300 to $400.
Recent auction prices
Prices for toys from the Spilhaus Collection, sold July 3, 1993, by Noel Barrett Antiques & Auctions Ltd. (P.O. Box 1001, Carversville, Pa. 18913,  297-5109) include any applicable buyers' premium.
* "Popeye the Pilot," circa 1940s, lithographed tin wind-up by Marx, with original box, American, 8 inches long, excellent condition, $1,045.
* "Mortimer Snerd Drummer," circa 1940s, lithographed tin wind-up by Marx, American, 8 inches long, very good condition, $687.50.
* "Moon Mullins Hand Car," circa 1940s, lithographed tin wind-up by Marx, American, 6 inches long, very good condition, $440.
* "Donald Duck Crazy Car," circa 1950s, lithographed tin wind-up with plastic figure by Marx, with original box, American, 6 inches long, excellent condition, $522.50.
* "Mickey Mouse Hurdy Gurdy," circa 1930s, lithographed tin wind-up, German, 6 inches long, fair condition, $330.
* Magician under glass dome, circa 1825, clockwork automaton, French, 24 inches high, excellent condition, $7,150.
* "Bond Bread Wagon," with original driver and bread crate, late 19th century, wood, by Schoenhut of Philadelphia, very good condition, $3,300.
Have a question about an antique or collectible? Write to the Solis-Cohens, P.O. Box 304, Flourtown, Pa. 19031-0304, enclosing a clear photo of the whole object and all marks. Photos can't be returned. Although personal replies are not possible, questions of general interest will be answered in this column.
' Solis-Cohen Enterprises