Just out of interest I did a little test to see what a 10 bit multiplier would fit into and using this very simple code it takes about 190 LE's in an altera device, of course youve got to bolt on an interface but it would run at about 70 Mhz even in the slowest device available.

library IEEE;
Use IEEE.std_logic_1164.all;
use ieee.numeric_std.all;
entity test is
port(a : in signed(9 downto 0);
b : in signed(9 downto 0);
q :out signed(19 downto 0));
end test;

architecture rtl of test is
begin
q<=a*b;
end rtl;