Your search for "mustard yellow" revealed the following:

Grinch "Merry Grinchmas" Foil Balloon 18 IN (46cm)
New
Out stock
$3.00
Sponge Bob Square Pants Balloon Bouquets | Set 5
New
Out stock
$18.50
Goldenrod | 16 INCH | Qualatex Latex Balloons | Package 6
New
Out stock
$4.80
Taco Shaped Party Paper Napkins | Package 25
New
Out stock
$8.00
Pineapple Balloons | 31 INCH
New
Out stock
$6.50
Sesame Street Elmo and Cookie Monster Balloon | 42 INCH | Licensed
New
Out stock
$7.00
Pastel Fringed Party Paper Napkins | Package 24
New
Out stock
$8.00
Goldenrod | 5 INCH | Tuftex Latex Balloons | Package 10
New
Out stock
$1.95
Smiley Face Lemon Balloon | 29 INCH
New
Out stock
$6.95
Bee Latex Balloons | Package 6
New
Out stock
$4.50
Lemon Slice Balloon | 14 INCH
New
Out stock
$3.50