Had to do some serious nesting, but this seems to work:
=IF(AND(ISNUMBER(SEARCH("~*", A1)), ISNUMBER(SEARCH(" ", A1))=FALSE), "",
IF(AND(ISNUMBER(SEARCH("$", A1)), ISNUMBER(SEARCH(" ", A1))=FALSE), "",
IF(ISNUMBER(SEARCH(" ", A1)), TRIM(RIGHT(SUBSTITUTE(A1, " ", REPT(" ", LEN(A1))), LEN(A1)))...